Connecter for electrical appliances



H. G. BAKER CONNETER FOR ELECTRICAL APPLIANCES Jan. 24, 1933.

Filed MaIQh -1. 1930 @yf W A W d Patented Jan. 24, 1933 UNITED STATES HENRY G. BAKER, OF DES MOINES, IOWA CONNECTER FOR ELECTRICAL APPLIANCES Application led March 1,

This invention relates to an improvement in connecters for electrical appliances, such as sad irons, toasters, percolators and other electrical household appliances employing a pair of spaced contact studs for receiving and similar connection to electric line wires.

An object of the invention is to provide a connecter which may be employed substantially universally on'such appliances.

Another and most important object of the invention is to provide a connecter for electrical appliances which is so constructed and arranged as to insure a firm gripping contact with the contact stud of the appliance under any and all conditions, whereby arcing and over-heating of the component parts of the connecter is prevented.

Still another obj ect of the invention is to provide a connecter having a pair of rigidly mounted contact plates and a pair of spring pressed gripping levers coacting therewith, said members being constructed of heavy non-resilient material, the gripping engagement being effected by means of separate springs located at points remote from the contact points so that the spring pressure means are not aEected by heat radiated from the appliance or produced at the Contact points.

A further object of the invention is to provide a connecter which is provided with ample means for permitting a circulation of air about the tension means to reduce the tendency for overheating.

Another object of the invention is to provide a connecter so constructed and arranged that the electric line wires enter the insulating shell at one lateralside thereof and in such manner as to reduce the danger of burning the hand or wrist of the operator in use, to prevent kinking, bending or injury to the wires and also tending to cause the wires to extend laterally and drape over the side of u an ironing board or table, particularly when the connecter is employed in connection with a sad iron.

A further object of the invention is to provide a connecter which is durable and long lived and also particularly efiicient in use. the 'G0 parts all being of sturdy construction and so 'in-g shown in position for use.

1930. Serial No. 432,515.

arranged as to greatly reduce the danger of deterioration on account of the radiation of heat.

l-Vith these and other objects in view my invention consists in the construction, arrangement and combination of the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and i illustrated in the accompanying drawing, in which:

Fi gure-l is a perspective View illustrating my improved connecter as mounted for use on a conventional type sad iron, the iron be- Figure 2 is a side elevation illustrating the iron tipped back to inoperative position and showing particularly the advantageous position of the connecter when the iron is so placed.

Figure 3 `,is an internal view of the connecter with the two parts of the shell in lseparated condition.

Figure 4 is a longitudinal section of the device on the line 4.-'-4 of Figure 3 showing the contact members in operative position.

The type of connecter ordinarily employed for household and similar electrical appliances are constructed with light weight resilient contact members for yieldingly engaging the contact studs of the appliances. These. light weight spring contacts or clips are incapable of withstanding a great amount of heat and on this account they soon lose their resiliency and afford only a weak en- .gagement with the studs, whereby -arcing occurs. This condition soon leads to burning of the studs as well as of the clips so that the contact condition rapidly becomes worse and a very unsatisfactory condition results. This not only leads to injury to the other parts of the connecter or of the appliance itself but it also constitutes a very serious menace to radio reception because of the resulting electrical interferences. Furthermore, the ordinary types of connecters have very little range of adaptability to contact studs of different appliances because these studs are of different sizes and shapes and most of the connectel's even fail to make proper contact of 100 some of the studs when they are new. It is obvious from what has'been said heretofore that this condition will rapidly become worse on account of burning.

My improved connecter is so constructed that it will make a proper contact with studs of dii'erent size and shape not only when they are new but also when they may become reduced in size by wear or burning.

Furthermore the contact members are of very sturdy construction so that they will withstand excessive heat from the appliance or from any arcing that may occur, and in addition to this the spring tension means are located at points remote from the contact points so that they are not affected by the heat. They are also provided with ample means permitting the circulation of air, particularly about the tension devices.

My connecter includes an elongated shell of suitable insulating material of high heat resisting qualities and it is formed of two similar members which I have designated by the characters A and B. The similar members A and B may be connected by any conventional means such as screws 10.

The shell member A is formed with a recess 12 occupying the greater portion of its length and opening to its inner face. For the greater part of its length the recess 12 is divided by a longitudinal partition 14 which extends to the forward end of the shell.

Contact plates 16 and 18 `are mounted in therecess '12 on opposite sides of and separated by the partition 14. The contact plates may be formed of brass or other suitable contact material and are quite heavyand sturdy in construction, possessing no inherent resilience. The Contact plates are held rigidly in place by screws 20 and 22 respectively and preferably have their back sides resting against the shell member A so that they are stationary and immovable. The forward end portions of the contact plates16 and 18 are grooved or otherwise suitably shaped to engage the Contact studs of an appliance.

The shell members A and B are together formed with a cylindrical recess 24 extend ing at an oblique angle and opening to one lateral side of the shell. The recess 24 receives the ordinary attaching cord such as- 2.6 and the line wires 28 and 30 of said cord pass into the recess 12, on opposite sides of the partitions 14, and are attached at their ends to the screws 20 and 22.

The cord is protected by means of the usual coil spring 32 adjacent the connecter and said sprin -enters the recess '24 and has an enlarge portion seated in an enlarged portion 34 of the recess. The shell members A and B are together formed at their forward ends with spaced apertures 36 and 38 to permit the entrance `of spaced contact studs 40 of an electrical ap-l pliance such as a sad iron 42, whereby said studs may be permitted to fall into engage-v spaced longitudinally extending recesses. 44

and 46 separated by a partition 48 which is in line with and adapted to engage the partition 14 of the shell member A.

Mounted in the recesses 44 and 46 aregripping levers 50 and 52. These levers preferably are made of steel and are quite sturdy in construction, possessing no inherent resile ience.

The gripping levers 50 and 52 are mounted opposite the contact plates 16 and 18 and are adapted to coact therewith, being formed at their forward end portions with substantially V-shaped grooves or sides adapted to coact with the grooved portions of the contact plates in engaging position for the studs 40. The recesses 44 and 46 of the shell member B are formed at their rear ends with portions 44 and 46 which are enlarged or deepened to permit oscillation of the levers 50 and 52. f

The gripping levers 50 and 52 are formed on their back sides with substantially semispherical fulerum. points 54 which engage and rock in semi-spherical seats 56 formed in the shell. member at intermediate points of the longitudinal recesses 44 and 46.

A pair of steel coil springs 58 and 60 are mounted between'the shell members A and B,-

each having one end receivedin a cylindrical recess formed at the inner face of the shell member A at its rear end. The cylindrical recesses are designated by the numerals 62` and 64.

When the parts of the device are assembled the springs 58 and 60 are placed under considerable tension, and are engaged with the rear ends of the gripping levers 50 and 52 respectively whereby such portions of the levers are pressed into the enlarged portions 44 and 46 of the recesses and the forward ends of the levers are/urged toward the contact plates 16 and 18.

The yielding mounting of the gripping levers 50 and 52 permits the forward ends o the levers to yield sufficiently for the studs 40 of an electrical appliance to pass between them and the contact plates and the springs l58 and 60 serve at all times to provide a firm and secure grip of the levers against the studs. This provides a good and proper contact with the studs regardless of variations in the size and cross sectional shape thereof, and for that reason my connecter may be regarded as subl fstantially'universal for appliance of the character 'set forth.

This firm' spring pressed, gripping engagement with the contact studs prevents arcin and overheating within the connecter an thus eliminates a common cause of injury to the component parts. Because of the fact that the contact plates 16 and 18 and the gripping levers 50 and 52 are of heavy, sturdy construction and need not be made of spring metal, they are capable of enduring considerable heat Without deterioration. The location of the compression springs 58 and 6() at points remote from the points of engagement with the contact studs serves to remove them -from the area where excessive heat may occur and thus eliminates the danger of injury to the tension means. This arrangement also piaces a greater degree of gripping power at the outer ends of the gripping levers, as compared with structures in which springs are placed close to the pivots.

In order to further eliminate any tendency which may occur toward overheating, I have considered it advisable to provide means for the circulation of air through the shell. I have therefore formed the shell members A and B with air openings 66 located adjacent the rear portions of the gripping levers 50 and 52 and also with air openings 68 located substantially7 axially and at both ends of the compression springs 58 and 60.

vSince the contact plates 16 and 18 are mounted in stationary position and are firmly backed by the shell member A, their ability to make good contact with the studs 40 is not adected by the heat which ordinarily tends to ruin the spring contact clips of the common form of connecters.

The gripping levers 50 and 52 are of sufficient transverse dimensions to give them ample rigidity to hold the contact plates firmly against the studs even if they should become excessively heated. The gripping levers preferably are made of steel so that they act as very poor conductors in transmitting heat from the studs to the springs 58 and 60.

The springs 58 and 60 preferably are made of steel so that they are capable of Withstanding temperatures that would be riinous to the presenttypes of spring clips and they also provide a much quicker and more effective spring action than can be obtained from spring clips or contacts made of light material and having inherent resilience. This method of applying tension also permits the gripping levers 50 and 52 to have a Wider range of action than .is possible with inherently resilient clips. This is of advantage because it enables the levers to open sufficiently wide to receive the large size contact studs of various appliances, and on the other hand, permits them to come close enough to the contact plates to properly grip the smallest contact plates. This range of action also permits the proper gripping of fiat contact plates as Well as those which are circular in cross section.

The oblique arrangement of the service cord 26 as it enters the shell at one side thereof is of advantage for sevelal reasons. It

permits the satisfactory use of this connecter with respect to a sad iron 42 of the tip-back type as illustrated in Figure 2, and the iron may be tipped back to an inoperative position without kinking, or any .undesirable bending of the service cord which often results in the breaking of the Wires. Furthermore, the location of the cord at one side of the connecter removes it from possible contact with the Wrist of the user thus preventing danger of burns. In addition to this the lateral rearwardly directed position of the cord tends to cause the cord to drape itself over the farther edge of a table or ironing board rather than to pile up behind the iron as with the ordinary type of connecter in which cord enters at the rear end of the shell.

Some changes may be' made in the construction and arrangement of the parts of my device Without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents, which may be reasonably included within their s cope.

I claim as my invention:

1. A connecter for electrical appliances,

comprising an insulating shell, a pair of grooved contact plates rigidly and immovably mounted in the shell and in contact therewith substantially throughout their lengths, means for connecting said plates to line Wires, a pair ofv rigid and inflexible grooved gripping levers having fulcrum points bearing against a portion of the shell itself and adapted to coopera-te with the contact plates for securely gripping the contact studs of an electrical appliance, and compression springs engaging said levers for urging them toward the Contact plates.

2. A connecter for electrical appliances,

comprising an insulating shell, 'a pair of grooved contact plates rigidly and immovably mounted in the shell, means for connecting said plates to line Wires, a pair of grooved gripping levers having fulcrum points immovable with respect to the shell, said levers being of rigid construction and adapted to cooperate with the contact plates for securely gripping t-he contact studs of an electrical appliance, said levers being entirely independent of said contact plates'so Jfar as direct physical connection is concerned,

and compression springs engaging said levers for urging them toward the contact plates,

said springs being located at the remote end of the shell from the points of contact with the appliance, and being spaced material and considerable distances from said fulcrum points to afford ample gripping -poWcr at the outer ends of said gripping levers.

3. A connecter for electrical appliances, comprising an insulating shell, a pair of grooved contact plates rigidly mounted in the shell and occupying only the forward portion thereof, means for connecting said plates to line Wires entering the shell at a point rearwardly of said plates, a pair of 5 rigid steel gripping levers fulcrumed between their ends, said levers being grooved at one end to coact with said contact plates, said levers being of greater length than said plates and projecting beyond the rear ends thereof, and a pair of coil steel compression springs engaging the rearwardly projecting ends of said levers for urging their grooved portions toward the contact plates, whereby contact studs of an electrical appliance may be firmly gripped between the levers and plates and whereby the tension means is rendered less subject to the action of heat engendered by the appliance or at the contact points.

4. A connecter for electrical appliances, comprising an insulating shell, a pair of grooved contact plates rigidly mounted in the shell, means for connecting said plates to line wires, a pair of grooved gripping levers fulcrumed in the shell and adapted to cooperate with the contact -plates for securely gripping the contact studs of an electrical appliance said levers being of materially greater length than the plates and projecting beyond their rear ends ,and compression coil springs engaging the projecting rear ends of v` said levers for urging them toward the contact plates, said shell being formed with air openings arranged centrally of said springs.

5. A connecter for electrical appliances, comprising an elongated shell of insulating material having spaced openings in one end to receive the contact studs of an appliance, a pair of rigidly mounted, grooved contact plates, means for connecting said plates to electric line wires, a pair of rigid and inflexible gripping levers formed with semispherical fulcrum points between their ends for rockably` engaging the inner face of said a shell, said levers 4being grooved at one end to coact with said contact plates for engaging contact studs, and springs engagingthe opposite ends of said levers, at points remote from the contact portions, for urging the grooved portions thereof toward the contact plates.

6. A connecter for electrical appliances, comprising an elongated shell of insulating material having spaced openings in one end to receive the contact studs of an appliance, a

'pair of rigidly mounted, grooved contact plates', means for connecting said plates to electric line wires, -a pair of rigid and iniexible gripping levers fulcrumed between their ends'in said shell, said vlevers being grooved atone'end to coactvwith said contact plates for engaging contact studs, and coil springs engaging the o posite ends of said levers, at points remote rom the contact portions, for l .said springs to permit the circulation of air therethrough for coolin purposes. A

HE RY G. BAKER.l 

